SAMLEX AMERICA INC. | 27
7.16 SIZING THE INVERTER BATTERY BANK
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There are a few basic formulae and estimation rules that are used:
1.
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2.
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quired from the 12V batteries is the AC power delivered by the inverter to the load
in Watts (W) divided by 10 & for an inverter running from a 24V battery system, the
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by the inverter to the load in Watts (W) divided by 20.
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The first step is to estimate the total AC watts (W) of load(s) and for how long the
load(s) will operate in hours (H). The AC watts are normally indicated in the electrical
nameplate for each appliance or equipment. In case AC watts (W) are not indicated, For-
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of this calculation for a 12V inverter is given below:
Let us say that the total AC Watts delivered by the inverter = 1000W.
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Next, the energy required by the load in Ampere Hours (Ah) is determined
.
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Now, the capacity of the batteries is determined based on the run time and
the usable capacity.
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And finally, the actual desired rated capacity of the batteries is determined
based on
the fact that normally only 80% of the capacity will be available with respect to the
rated capacity due to non availability of ideal and optimum operating and charging
conditions. So the final requirements will be equal to:
SECTION 7 |
General Information on Lead Acid
Batteries
